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Multi-functional diffraction gratings have found broad applications in laser processing, medicine, beam manipulation, etc. However, based on the existing schemes there are still some challenges in fabricating the diffraction gratings with the controllable and arbitrary diffraction intensity of each order, multiple phase distribution, and polarisation of the output. Here, we propose a new phase mixing algorithm based on the random binary matrix and describe the theoretical foundation and experimental realisation of the proposed scheme. Using the new algorithm, several phase-mixing devices were fabricated, and the experiment verified the relationship of the light intensity, polarisation, phase and the algorithm. Our approach is practical to mix the phases of several diffraction gratings to realise the controllable diffraction orders, offering an innovative idea for the research of the liquid crystal phase mixing devices. [ABSTRACT FROM AUTHOR]

This study proposed a novel method based on self-interference polarisation pantograph (SiPPer) for fabricating Pancharatnam-Berry (PB) devices. The SiPPer method was composed of a standard Cassegrainian system and a polarization patterned template. Based on the self-interference effect between the ordinary and extraordinary components after the birefringence template, all the polarization information were losslessly transferred to the focal plane on which a photosensitive polarization sample was placed. All PB devices are compatible with this method, including polarization grating, q-plate, q-lens, etc. The SiPPer method indeed lowers the requirement on the exposing source, particularly on the parameters of coherence length and linewidth. To verify and evaluate the properties of the SiPPer method, two typical examples, liquid crystal polarization grating and q-plate, were designed and fabricated according to the standard processing. And the experimental results showed fabulous agreement with the theoretical simulation results. [ABSTRACT FROM AUTHOR]

Edge imaging is now an efficient way capable of demonstrating boundary features of an object, which is widely applied in optical imaging, robot vision. In this article, we propose an electrically regulated wedge liquid crystal (LC) cell for edge imaging based upon the combination of the large birefringence of LC and its electro-optic tunable characteristic, and its imaging principle of this element has been theoretically analysed. The experimental results wonderfully manifest that this method can achieve broadband edge imaging and realise real-time mode switch between edge image and original image which can be controlled by a proper voltage. We also demonstrate that the function for achieving electrically controllable resolution is feasible in theory. [ABSTRACT FROM AUTHOR]

An organic-inorganic hybrid polyoxometalate (POM) based on bi-nuclear copper complexes and Dawson-type phosphotungstate (POT) [CuL(H2O)][CuL]2[P2W18O62]·3H2O (abbreviated as CPW) (L = 2-(1H-pyrazol-3-yl)pyridine) was synthesized and structurally characterized by IR spectrum, and single-crystal X-ray diffraction. Structural analysis indicated that CPW is nanoscale molecule and extends into a two-dimensional layer, in which three bi-nuclear copper complexes are substituted at different sites of Dawson-type POT and joined adjacent POT fragments together. Notably, CPW can efficiently catalyze the production of reactive oxygen species. [ABSTRACT FROM AUTHOR]

In this article, we proposed a new class of light beam which arose from the combination of the symmetric Airy beams and vortex or vector beams. We called them symmetric Airy vortex beam and symmetric Airy vector beam. In our experiments, we combined vortex phase and symmetric spatially cubic phase to fabricate liquid crystal q-symmetric-Airy plate. It can directly generate the symmetric Airy vortex or symmetric Airy vector beams by controlling the polarisation of incident Gaussian beam. This work may provide a versatile candidate for many potential optical applications in the areas of optical micromanipulation, optical communication and paves the way for the future researches of symmetric Airy vortex and symmetric Airy vector beams. [ABSTRACT FROM AUTHOR]

In this paper, we extended the methods for fabricating phase-integrated liquid crystal optical elements by interfering of orthogonal circularly polarised beams with different PB phase and generalised those methods as Pancharatnam-Berry (PB) phase interference theory. The generalised theory exhibits two kinds of interference ways. The first way takes place when various PB optical elements (PBOEs) are sequentially illuminated by a linearly polarised light in half-wave condition. The second way happens when the first PBOE is illuminated by a circularly polarised light in quarter-wave condition while the following PBOEs are in half-wave condition. The fabrication of fork polarisation gratings based on this generalised theory is used to confirm the two different interference ways. The generalised theory can better describe the interference of orthogonal circularly polarised beams with different PB phase and can be widely used for fabricating phase-integrated liquid crystal optical elements using existing PB phase device, which may promote the development and extensive applications of the PBOEs. [ABSTRACT FROM AUTHOR]